It is a known fact that perishable goods can be kept for longer periods while in a clean atmosphere containing a minimum of oxygen and humidity. Food exposed to the influence of oxygen and humidity quickly loses its taste, flavor and texture. For this reason preserves are packed in a vacuum, as well as granular foods which are packed in an airtight package. These preserves and packages are manufactured under vacuum. In fact, many chemicals, especially pharmaceutics, are nowadays preserved from the influence of humidity and oxygen, by keeping them enclosed in vacuumized containers, or in containers filled with nitrogen.
In the old times most households had an apparatus for preparing preserves of fruit and vegetables. This apparatus was in the form of a large pot closed by a cover and partly filled with water. A number of glass jars with gasketed covers filled with fruit or vegetables with a certain amount of water were placed into that pot which was then brought to boiling. The water in the jars created steam and after cooling the vacuum created in each jar sucked the cover tightly onto the opening and the food was thus preserved for a long period of time.
A later development of an evacuating system included containers provided with a check-valve and a tube connector in the lid or cover. Air was pumped out by a manually or mechanically operated pump connected to the container by a flexible hose. This practice never found many friends because of the time required for evacuating every container separately, the cost of the valve and the danger of pollution by way of the valve.
With increasing industrialization these apparatus were stored away and home-made preserves disappeared from the dinner table. The main reason was the time and effort required in making these preserves, while the supermarket could supply the desired--or a similar--product in a tin. Not only is the home-made product of higher quality, since it used to be made of selected fruits and vegetables, but it used to be prepared to the family's taste, while tinned food is not always of first choice, not to mention its higher price.
For these reasons it is the object of the present invention to provide a domestic apparatus capable of preparing preserves in a matter of seconds with a minimum of effort
It is another object to provide a domestic apparatus for making preserves of any foodstuff or product, either in raw state or precooked.
It is a foremost object to preserve food in jars or other containers to be closed by a simple cover or screwcap without any special checkvalves.
Still another object is to provide a domestic apparatus which is operable by anybody, without danger of being scalded by steam or boiling water.
It is an additional object of the invention to use for storage of foodstuff and other products any kind of vessel, jar, bottle or container that can be closed by any kind of lid or cover provided with a gasket to seal the opening of the vessel.
And it is a final object to provide the equipment at a price which will make it available for most households.